The research in this project is aimed at determining the mechanism by which rhodopsin excites the visual receptor. Characteristics of rhodopsin which reveal general properties of membrane structure and function are also being investigated. The techniques employed include flash photometry, microspectrophotometry, osmotic permeability studies, atomic absorbance observations of ion content, & indicator dye techniques for ionic activity measurements. BIBLIOGRAPHIC REFERENCES: Petersen, D.C. and Cone, R.A., The Electric Dipole Moment of Rhodopsin Solubilized in Triton X-100 Biophysical Journal 15 1181-1200 (1975).